How to interact with a Smart Contract on private network using Web3 js

Question

I have deployed my smart contract on private network using Mist browser and Geth. Following is my script:

if (typeof web3 !== 'undefined') {
            web3 = new Web3(web3.currentProvider);
        } else {
            // set the provider you want from Web3.providers
            web3 = new Web3(new Web3.providers.HttpProvider("http://localhost:8545"));
        }
web3.eth.defaultAccount = web3.eth.accounts[0];
var CoursetroContract = web3.eth.contract(YOUR ABI);

var Coursetro = CoursetroContract.at('PASTE CONTRACT ADDRESS HERE');
console.log(Coursetro);

Answer 1

Once you set up infura you can use the portal URL that they return to create your provider. Edit you script and put the infura URL in the place where I wrote <your infura.io url here> and that should configure your fallback if the user doesn't have a current provider

if (typeof web3 !== 'undefined') {
            web3 = new Web3(web3.currentProvider);
        } else {
            // set the provider you want from Web3.providers
            web3 = new Web3(new Web3.providers.HttpProvider(<your infura.io url here>));
        }
web3.eth.defaultAccount = web3.eth.accounts[0];
var CoursetroContract = web3.eth.contract(YOUR ABI);

var Coursetro = CoursetroContract.at('PASTE CONTRACT ADDRESS HERE');
console.log(Coursetro);